Integrable semi-discretization of the massive Thirring system in laboratory coordinates

Several integrable semi-discretizations are known in the literature for the massive Thirring system in characteristic coordinates. We present for the first time an integrable semi-discretization of the massive Thirring system in laboratory coordinates. Our approach relies on the relation between the continuous massive Thirring system and the Ablowitz-Ladik lattice. The Backlund transformation for solutions to the Ablowitz-Ladik lattice and the time evolution of the massive Thirring system in laboratory coordinates are combined together in the derivation of the Lax system for the integrable semi-discretization of the massive Thirring system.Comment: 10 pages, 0 figure

Leukocyte ratios are useful early predictors for adverse outcomes of COVID-19 infection

Leukocyte biomarkers, including the neutrophil-to-lymphocyte (NLR), monocyte-to-lymphocyte-(MLR), platelet-to-lymphocyte (PLR) ratios and systemic immune-inflammation index (SII) have been associated with severity and mortality of patients with COVID-19. The purpose of this study was to evaluate the association of baseline leukocyte biomarkers calculated in the emergency department (ED) with the disease severity and mortality. This was a retrospective cohort study that evaluated 1,535 (mean age 57+18 years) patients with SARS-CoV-2 infection in the ED of a single reference center. Outcomes were severity, defined as intensive care unit (ICU) admission requirement, and in-hospital mortality. All leukocyte biomarkers were calculated in the ED before the hospital admission. Their ability to predict the severity and mortality was measured using receiver operating characteristic (ROC) curves. Severity and mortality were observed in 30.9% and 12.6% of the patients, respectively, and were significantly correlated with NLR, MLR, PLR and SII, but only NLR was independently associated with both outcomes on multivariate analysis. Analysis of ROC curves revealed that NLR (0.78 for severity and 0.80 for mortality) and SII (0.77 for severity and 0.75 for mortality) had the best ability to predict mortality, when compared to other ratios. The highest AUC was observed for NLR, employing cut-off points of 5.4 for severity and 5.5 for mortality. Leukocyte biomarkers, particularly NLR, are capable of predicting the severity and mortality of patients with SARS-CoV-2 infection and could be important adjunct tools to identify patients in the ED that are more prone to develop adverse outcomes

Chronic hepatitis C and fibrosis: evidences for possible estrogen benefits

The main injury caused by hepatitis C virus is the hepatic fibrosis, as a result of a chronic inflammatory process in the liver characterized by the deposit of components from the extracellular matrix. The fibrosis development leads to the modification of the hepatic architecture, of the hepatocellular function and to irregularities in the microcirculation. The tissue remodeling process observed in fibrosis has stellate cells, located at the space of Disse, as main acting agents. These cells, in response to a harmful stimulus, undergo phenotypic changes from non-proliferating cells to proliferating cells that express a- smooth-muscle actin (a-SMA), a process called as transdifferentiation. There are evidences that the oxidative stress is involved in the chronic liver disease and serves as bond between the injury and the hepatic fibrosis. A number of studies suggest that the estrogen, at physiological levels, presents an antifibrogenic action probably through an antioxidant effect, decreasing the levels of lipid peroxidation products in the liver and blood, thus inhibiting the myofibroblastic transformation of stellate cells and contributing for gender-associated differences in relation to the fibrosis development. The aim of this paper was to describe data from literature concerning the interaction between chronic hepatitis C and estrogens, pregnancy, use of oral contraceptives, menopause and hormone reposition therapy

Hepatoportal sclerosis related to the use of herbal and nutritional supplements. Causality or coincidence?

Introduction and aim. Non-cirrhotic idiopathic portal hypertension (NCIPH), also known as hepatoportal sclerosis (HPS) is a disease of uncertain etiology. However, many pathophysiological mechanisms has been postulated, including thrombophilia, chronic recurrent infections and exposure to drugs or toxins. In this context, it appears to be of multifactorial etiology or resulting from a portal vascular endothelium aggression. It is important to consider whether the use of dietary supplements and herbs can trigger or contribute to the occurance of HPS. We report a possible association of HPS with the consumption of herbal and / or dietary supplements.Material and methods. We describe two cases of HPS in patients without known etiology causes associated with this disease.Results. Both patients were females who were diagnosed with HPS following the consumption of Herbalife® products and putative anorexigenic agents in the herbal infusions. Image-based analysis and the assessment of the histopathological alterations found in the livers confirmed the diagnosis. The histopatological analysis of liver samples from both patients showed portal tracts enlarged by fibrosis with disappearance or reduction in the diameter of the portal vein branches. In many portal tracts, portal veins branches were replaced by aberrant thin-walled fendiforme vessels. The bile ducts and branches of the hepatic artery show normal aspects.Conclusion. After the exclusion of other etiologic factors and a comprehensive analysis of clinical history, consumption of Herbalife® products and anorexigenic agents was pointed-out as a puttative predisposing factor for the development of the disease

Hepatite aguda criptogênica: uma entidade heterogênea com possibilidades de complicações

Hepatites agudas ou crônicas de causas não definidas constituem um problema na prática de médicos clínicos e gastroenterologistas. Apesar do desenvolvimento de sofisticados testes laboratoriais, uma proporção significativa das hepatites ainda permanece com causa não-determinada. São as chamadas hepatites criptogênicas ou hepatites não A-E. Possíveis etiologias são sugeridas: vírus desconhecido, doenças metabólicas ou hepatite auto-imune de apresentação atípica. Recentemente, nosso grupo demonstrou que, num centro de referência no Brasil, 17% dos casos de hepatites agudas são criptogênicos, com alguns aspectos sugerindo etiologia viral. Nós relatamos quatro casos de hepatite aguda criptogênica, demonstrando a heterogeneidade dessa condição clínica associada à possibilidade de complicações, o que justifica uma criteriosa investigação epidemiológica, clínica e laboratorial, assim como o acompanhamento desses pacientes

Comparative study of Hepatitis C virus genotypes 1 and 3 in Salvador, Bahia

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2012-12-10T19:25:14Z No. of bitstreams: 1 Codes, L et al Comparative study of hepatitis....pdf: 51766 bytes, checksum: f40158fc353f9d150213a6cd057d9f75 (MD5)Made available in DSpace on 2012-12-10T19:25:14Z (GMT). No. of bitstreams: 1 Codes, L et al Comparative study of hepatitis....pdf: 51766 bytes, checksum: f40158fc353f9d150213a6cd057d9f75 (MD5) Previous issue date: 2003Universidade Federal da Bahia. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilUniversidade Federal da Bahia. Salvador, BA, BrasilInstitut National de la Santé et de la Recherche Médicale. Lyon, FranceFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilInstitut National de la Santé et de la Recherche Médicale. Lyon, FranceFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilUniversidade Federal da Bahia. Salvador, BA, BrasilHepatitis C virus displays a high degree of genetic mutation, with considerable heterogeneity, motivating clinical and biomolecular investigations. It is necessary to understand the effects of genotypes on the course of the disease, as well as their peculiarities at the regional level. Objective: The study objective was to compare epidemiological, biochemical and histological aspects of hepatitis C virus genotypes 1 and 3 in Salvador, Bahia. Study Design: Data were collected retrospectively from outpatient medical records. Materials and Methods: 127 patients with positive anti-HCV results were selected, based on detectable RNA-HCV (RT-PCR) of genotypes 1a, 1b and 3a. Results: Thirty-nine (30.7%) individuals were infected by subtype 1a, 45 (35.4%) by subtype 1b and 43 (33.9%) by subtype 3a. Most (73.2%) patients were male, with an average age of 47.8 years. The subtype 1b-infected patients had the highest average age (512 ±11.17; P=0.09). The use of illicit injected drugs was more frequent among subtype 3a infected individuals when compared with genotype 1 (6/43; 14% and 3/84; 3.6%, respectively; P=0,06). No significant differences were found for other epidemiological characteristics. Average values for GT, AST, ALT and ferritin did not differ between the groups (64, 78, 109, 276, respectively). Thyroid dysfunction occurred in 7/30 (23.3%) of those infected by genotype 3 (P=0.05). Cryoglobulinemia was also more frequent in this group (5/13, 38%, P=0.02). Most patients presented limited necro-inflammatory activity, stages 2 and 3 by the METAVIR Classification. In some cases, dissociation was noticed between inflammatory activity and fibrosis. No significant differences were found in the histopathological findings of the various genotypes. Younger patients had a significantly smaller degree of necrosis in stomatocytosis (P=0.032) and fibrosis (P=0.012). Intense parenchymatous activity and lymphoid follicles were more frequent among alcohol consumers (P=0.06 and P=0.04, respectively). Conclusions: In Bahia, genotype 3 dissemination seems to be associated with illicit drug use. The disease evolution depends on a function of complex interactions between virus and host. Age and alcohol consumption stand out as important variables in the development of cirrhosis